Extended shelf life ricotta cheese blends and process for preparing

ABSTRACT

The present invention provides a method of preparing a spreadable stabilized and seasoned cheese blend based on ricotta cheese, as well as the ricotta cheese blend composition, and a lasagna kit that includes the ricotta cheese blend, optional shredded cheese, tomato sauce, and uncooked lasagna. The method of stabilizing the ricotta blend includes the step of treating the blend at a temperature in the range of 160° F. to 170° F. for a time sufficient to confer to the blend a shelf life stability against the growth of  Clostridium botulinum  for at least 20 weeks. In additional aspects of the method, the cheese blend, and the kit, the cheese blend further includes an additive chosen from among a second cheese other than ricotta, salt, spices, herbs, an edible acid, and a preservative, or a mixture of any two or more of these additives.

FIELD OF THE INVENTION

The present invention relates to spreadable ricotta cheese blends thatare stable to storage at refrigerated temperatures for extended periodsof time. The invention further relates to methods of preparing thericotta cheese blend, and to meal or lasagna kits incorporating thericotta cheese blend.

BACKGROUND OF THE INVENTION

Food products that minimize the preparation time in the home withoutsacrificing flavor and texture are in great demand in contemporarysociety. Some pasta dishes can be made quickly in the home kitchen;others, however, require time-consuming preparation if made fromscratch. Lasagna, although a popular dish which contains flavorfulcomponents such as ricotta and other cheeses, herbs, spices, and atomato based seasoned sauce, does require significant preparation time.Other pasta dishes containing ricotta cheese, including, for example,stuffed shells, manicotti, and the like, are also popular but timeconsuming when prepared in the home kitchen. With the limited timeavailable in the modern family for food preparation, suchdishes—especially if prepared from scratch—are often eliminated from, oronly used sparingly in, the home menu. This is in spite of thepopularity of such pasta dishes with the public.

If the desired flavor, aroma, and texture are to be developed, suchpasta dishes must be made using fresh ingredients—including the ricottacheese ingredient—and prepared largely, if not entirely, from scratch.As an example of this burden, the lasagna noodles in a baked lasagnapreparation are typically cooked, or at least partially cooked, beforebeing layered with cheese and sauce ingredients. The pre-cooking of thenoodles, the arrangement of the various layers, and then the baking timerequires both significant time and effort. For this reason, lasagna andother similar pasta dishes are often not prepared in the modern familykitchen where time for meal preparation is often limited.

A prepackaged ricotta cheese blend and/or a complete lasagna kitcontaining all necessary ingredients (including prepackaged and seasonedricotta cheese blend) which are available for purchase in a retailgrocery store would be a great convenience in the preparation of a bakedlasagna dish. Its availability would significantly reduce the time andeffort required in the assembly of the layered lasagna preparation priorto baking. Such a prepackaged ricotta blend would require a treatment atthe time of packaging to ensure its stability during the shelf lifeprior to purchase, and after purchase, prior to its actual use. Extendedperiods of stability are required to achieve this objective. Moreover,the stabilized ricotta cheese blend would need to retain itsspreadability during the extended shelf life, so that it could easily belayered into a lasagna preparation prior to baking. Such a spreadableand stabilized ricotta cheese blend and seasonings would further reducepreparation time and provide further convenience for the consumer. Sucha stabilized, spreadable ricotta blend could be included as part of alasagna kit, offering still further convenience to the consumer.

There thus remains a need for a stabilized, spreadable ricotta cheeseblend which can be prepackaged for retail sale to the consumer. Therealso remains a need for a lasagna kit that includes the stabilizedricotta cheese blend as an important component thereof. The presentinvention addresses these needs.

SUMMARY OF THE INVENTION

The present invention provides a method of preparing a spreadablestabilized ricotta cheese blend, a stabilized ricotta cheese blendcomposition, and a lasagna kit that includes the stabilized ricottacheese blend, optional shredded cheese, tomato-based sauce, and uncookedor precooked lasagna noodles. The ricotta cheese blend is stabilized bytreating the cheese blend containing ricotta cheese and, optionally,other cheeses and/or ingredients at a temperature in the range of 160°F. to 170° F. for a time sufficient to provide a shelf life atrefrigerated temperatures against the growth of Clostridium botulinum ofat least 20 weeks. In an important embodiment of the method, the cheeseblend is treated at a temperature of about 165° F. Importantly, in spiteof the stabilization treatment, the ricotta cheese blend remainsspreadable at refrigerated temperatures.

The ricotta cheese blend may also contain other ingredients or additivessuch as, for example, one or more additional cheeses other than ricotta,salt, spices, herbs, edible acids, and preservatives. Preferably, amixture of two or more of these additives are employed in the cheeseblend. Suitable second or others cheeses to be included in the cheeseblend include, for example, Neufchatel cheese, Parmesan cheese, Romanocheese, Cheddar cheese, Mozzarella cheese, Provolone cheese, creamcheese, and a mixture of any two or more of these cheeses. Suitableedible acids include, for example, lactic acid, pyruvic acid, aceticacid, citric acid, tartaric acid, phosphoric acid, and the like.Suitable preservatives include sorbic acid and/or salts thereof. Ofcourse, other conventional additives, such as colorants, flavorants, andthe like, can be included in the ricotta cheese blend if desired.

DETAILED DESCRIPTION OF THE INVENTION

The present invention provides a spreadable, stabilized ricotta cheeseblend suitable for use in preparing pasta dishes such as baked lasagna,stuffed shells, manicotti, and the like. The ricotta cheese blend istreated to render it stable to microbiological contamination for atleast 20 weeks at refrigerated temperature (i.e., about 4 to 8° C.). Ingeneral, dairy products routinely sold at retail are stable for at leasta short time under proper storage conditions. However, the ricottacheese blends of the present invention advantageously include herbs,spices, and other additives to impart flavor to the baked lasagnapreparation. The inclusion of such herbs and spices, however, mayincrease the microbiological contamination or burden beyond that whichwould normally be present in the dairy composition itself. Thus, aricotta cheese blend similar to that of the present invention, exceptwithout the stabilization treatment provided in the present invention,could be a safety risk to the consumer. The stabilization treatment ofthe present invention significantly reduces that risk and provides asafe and stable product when stored and used properly.

Growth of pathogenic microorganisms, or of benign microbiologicalcontaminants whose presence results in rejection by consumers, must beprevented in a stabilized product such as the present ricotta cheeseblend. Pathogens include Clostridium botulinum, Escherichia coli,Listeria monocytogenes, Staphylococcus aureus, Salmonella typhimurium,and the like. More benign, but still objectionable, contaminants includeyeasts, molds and the like. In order to achieve stability against thegrowth of such microbiological contaminants during the extended shelflife, the ricotta cheese blend must be treated to kill anymicroorganisms present. In this invention, a criterion for shelf lifestability includes testing for the absence of C. botulinum growth duringchallenge experiments.

A common treatment intended to kill microbiological contaminantsincludes application of heat. Although a wide variety of such heatingprocedures are available to workers of skill in food science and may beemployed for this purpose, they differ significantly from the heattreatment employed in the present invention. In pasteurization, forexample, a liquid, such as a dairy liquid, is exposed to a temperatureof about 161° F. for a short period of time (i.e., about 15 seconds).Such a pasteurization, if applied to the ricotta cheese blend of thepresent invention, would not be sufficient to stabilize the treatedblend for an extended shelf life. In contrast, in the canning industry,for example, killing of microorganisms such as C. botulinum isaccomplished by heating at temperatures of about 300° F. for a period oftime in the range of about 3 about 6 seconds. Such a treatment, ifapplied to the instant ricotta cheese blend, would irreversibly alterthe structure of the ricotta cheese blend such that it would no longerbe spreadable and would adversely affect the organoleptic properties.Such a cheese blend would not be suitable for use in the intendedapplications of the present invention (i.e., preparation of lasagna andother pasta dishes).

The method of the present invention provides a heat treatment for thericotta cheese blend that surprisingly provides an extended shelf lifewith increased and improved spreadability. Thus, the ricotta cheeseblend of this invention is ideally suited for use in lasagna and otherpasta dishes prepared and consumed in the home. The stabilizationtreatment involves subjecting the ricotta cheese blend to a cooking stepin which the ricotta cheese blend is heated to a temperature in therange of from 160° F. to 170° F. for a time period sufficient to insurethat all of the ricotta cheese blend reaches the desired temperature andthat microorganisms that might be present are killed. Thus, moreefficient mixing and/or heat transfer will allow for shorter hightemperature treatment times. Generally, however, a high temperaturetreatment time of about 15 seconds to about 5 minutes is adequate.Preferably, treatment temperature is about 165° F. for a time period ofabout 1 to about 4 minutes. This heat treatment may be carried out inany conventional system (batch, semi-continuous, or continuous); forexample, the heat treatment can be carried out in a laydown cooker withsteam injection. The steam injection provides the means for attainingthe desired temperature effectively and controllably. The duration oftreatment at this temperature is sufficient effectively to killmicroorganisms present, such that no growth of microbiologicalcontaminants occurs in the stabilized product during a shelf life atrefrigerated temperature of at least 20 weeks and preferably at least 40weeks or longer. As those skilled in the art will realize, the length oftime required at the lowest temperature (i.e., about 160° F.) to insuresafety will be longer than that required at the higher temperature(i.e., about 170° F.); of course, the efficiency of mixing and heattransfer characteristics of the system must also be taken into account.Generally, for safety considerations, heat treatment times longer thanthe minimum needed or required for food safety considerations (e.g.,high temperature, short time pasteurization at about 18 seconds at 165°F.—assuming excellent mixing and heat transfer) are preferred so long asspreadability is not adversely effected.

As just noted, the duration of the heat treatment step is generallyabout 15 seconds to about 5 minutes. Excessive cooking (i.e.,significantly longer that the suggested heat treatment step) should beavoided since spreadability and flavor can be impaired. In actualapplication using the guidelines provided, it has been found that thestabilized ricotta blend prepared in this way is stable to growth ofmicroorganisms for at least 40 weeks. The lower limit of the heattreatment temperature and its duration are determined and/or controlledby the requirement to achieve effective killing of any contaminants thatmay be present.

The upper limit for the temperature and duration of the heat treatmentstep are determined and/or controlled by the requirements ofspreadability and flavor. Heating of cheeses generally leads to meltingand a significant change in the structure of the cheese product. In aricotta cheese blend, for example, such a change could lead to loss ofbody and/or texture and a loss of spreadability once the blend hascooled to ambient or refrigeration temperatures. Surprisingly, theinventors found that the ricotta cheese blend heat treated according tothe method set forth herein, not only retained spreadability uponcooling, but actually exhibited improved spreadability. Thus, thestabilized ricotta cheese blend is very spreadable. This attributeconfers usefulness as a prepackaged cheese spread for application to alayered lasagna preparation prior to baking and significantly reducesthe preparation time for a layered lasagne or other pasta product (e.g.,filled shells, manicotti, and the like). Without this spreadability, thestabilized ricotta cheese blend could not readily be used to prepare alayered lasagna or other pasta preparation. The upper temperature limitand the duration of the heating step are thus governed by therequirement of retaining the spreadability of the ricotta blend after itcools to ambient temperature and after storage at refrigeratedtemperatures for an extended period of time.

The duration of heat treatment required to achieve the prolongedstabilization of the present invention may vary with the size of thebatch, equipment design, and heat transfer characteristics of thetreatment equipment. Generally, mixing equipment offering high heattransfer and high mixing efficiency is preferred. One preferred heattreatment apparatus is a lay-down cooker with steam injection forheating. Of course other types of heat treatment apparatuses could beused so long as suitable heat transfer and mixing can be achieved.Generally, with a heat treatment in the range of about 160° F. to about170° F., the length of the heat treatment will be in the range of about15 seconds to about 5 minutes. As suggested above, good mixing is alsorequired—especially when treating large batches—since all of the cheeseblend must be exposed to the elevated temperatures.

Once the heat treatment has been completed, the stabilized ricottacheese blend should be packaged and cooled to refrigeration temperatures(generally in the range of about 4 to about 8° C.). Preferably, thestabilized ricotta cheese blend is hot-packed or hot-filled in anysuitable container and then allowed to cool to refrigeratortemperatures. Preferably for home use, the stabilized ricotta cheeseblend is packaged in single meal sizes. Such packaging could include,for example, glass or rigid plastic containers or, more preferably,sealable plastic pouches. More preferably, the stabilized ricotta cheeseblend is packaged in single meal or dish amount in a sealable, flexibleplastic pouch which is sealed to minimize the air within the package. Ifdesired, and to add further stability to the product, the stabilizedricotta cheese blend can be sealed under an inert atmosphere, modifiedgas atmosphere, and/or under aseptic conditions. During shipment and onretail shelves, the ricotta cheese blend should be stored under similarrefrigeration temperatures. Once purchased by the consumer, storageunder normal home refrigeration temperatures (which may be somewhatgreater than about 8° C.) is acceptable. The ricotta blend is stable forextended periods of time at any of these storage temperatures.

Additional, or supplemental, means of stabilizing the ricotta cheeseblend of the invention can contribute to the overall stability of thericotta cheese blend. Thus, for example, one or more edible acids may beincluded to provide a lower pH value in the blend. Sufficient edibleacid can be added to reduce the pH of the stabilized ricotta cheeseblend to between about 4.8 to about 5.2, and preferably to between about4.9 to about 5.1. Salt is also included to provide a high osmolality tothe blend as well as flavor. Additionally, one or more ediblepreservatives can be added to further increase the stability of thericotta cheese blend. Any of these supplemental means contributes to aloss of viability of any microbiological contaminants that may bepresent. Suitable edible acids include, for example, lactic acid,pyruvic acid, acetic acid, citric acid, tartaric acid, and comparableedible organic acids, and phosphoric acid. Any equivalent acid may alsobe used to contribute to the stabilization of the ricotta blend. Salt,when added, is generally added at levels of about 1 to about 2 percentby weight; preferably, the overall or finished salt content of the finalstabilized ricotta blend (added salt and salt entering with otheringredients) is in the range of about 1.8 to about 2.2 percent. Suitablepreservatives include, for example, sorbic acid and/or salts thereof.The stabilized ricotta cheese blend may further include flavoringcomponents such as herbs, spices, colorants, and the like for optimalconsumer acceptance. Generally, any such additives—especially those thatmight contain microorganisms—are blended with the ricotta cheese priorto the heat treatment step and, thus, are exposed to the heat treatmentstep. The edible acid can be added either before and/or after the heattreatment step to achieve the desired pH of the final product.

To achieve superior stability, the stabilized ricotta cheese blendshould contain sufficient edible acid to obtain a pH of between about4.8 to 5.2, salt, and a preservative. Generally, the stabilized ricottacheese blend preferably contains about 30 to about 90 percent ricottacheese, about 1 to about 2 percent salt, about 0 percent to about 30percent of the second cheese, about 0.1 to about 0.4 percent of thepreservative, sufficient edible acid to provide a pH of about 4.8 toabout 5.2 in the stabilized ricotta cheese blend; water, spices, andother additives (e.g., dried sweet whey, agglomerated corn starch, gum,and the like) make up the balance. Preferably, the stabilized ricottacheese blend preferably contains about 40 to about 50 percent ricottacheese, about 1 to about 2 percent salt, about 8 to about 12 percent ofthe second cheese, about 0.15 to about 0.2 percent of the preservative,sufficient edible acid to provide a pH of about 4.9 to about 5.1 in thestabilized ricotta cheese blend with the balance being water, spices,and other additives. Generally, the water or moisture content (includingadded water and water contained in the other ingredients) of the finalstabilized ricotta cheese blend is in the range of about 60 to 75percent with about 65 to 70 percent being preferred. Preferably thesecond cheese is Neufchatel cheese, Parmesan cheese, Romano cheese, or amixture thereof; the preservative is sorbic acid or a salt thereof; andthe edible acid is lactic acid, pyruvic acid, acetic acid, citric acid,tartaric acid, phosphoric acid, or mixtures thereof. Generally, thesecond cheese is used to impart desirable flavor and texturecharacteristics; likewise, additives such as agglomerated corn starchand gum (e.g., locust bean gum) can used to provide more favorabletexture characteristics.

The spreadability of the stabilized ricotta cheese bends of the presentinventions is an important characteristic. Conventional ricotta cheese,on the other hand, can be very difficult to spread over lasagna noodles.The improved spreadability of the stabilized ricotta cheese of thisinvention can be demonstrated using a TA-XT2 Texture Analyzer (StableMicroSystems, Haslemere, England). Using the Texture Analyzer, the forcerequired to penetrate a sample using a core of known material and crosssection is inversely proportional to the sample's spreadability. Inother words, the easier it is to penetrate a sample, the betterspreadability for the sample. A conventional ricotta cheese was comparedwith several ricotta blends of this invention; the penetration force isan average of three separate runs:

Sample Penetration Force (g) Conventional Ricotta 63 Italian Seasoned 21Ricotta Blend American Seasoned 38 Ricotta Blend

The preparation of the Italian seasoned ricotta blend is described inExample 2; the preparation of the American seasoned ricotta blend isdescribed in Example 3. The two ricotta blends of the present inventionhave significantly improved spreadability (i.e., lower penetrationforce) than conventional ricotta cheese.

In a further embodiment of the invention, a prepackaged, stabilizedricotta cheese blend is included in a lasagna kit to provide a completepackage for convenient preparation of baked lasagna in the home. Inaddition to the stabilized spreadable seasoned ricotta cheese blend ofthe invention, the kit can include a prepackaged, stabilized, seasonedtomato based sauce, and a package of uncooked or partially cookedlasagna noodles. If desired, a stabilized second cheese composition mayalso be included in the kit; such second cheeses include, for example,Neufchatel cheese, Parmesan cheese, Romano cheese, Cheddar cheese,Mozzarella cheese, Provolone cheese, cream cheese, and mixtures thereof.Such second cheese, if used, would preferably be in the form of shreds.If desired, such other cheeses as just mentioned can be included in thestabilized ricotta cheese blend. Preferably, each of the prepackagedingredients (i.e., stabilized ricotta cheese blend, tomato-based sauce,and lasagna noodles) are included in an amount suitable for thepreparation of a single lasagna dish. Similar kits can be prepared usingother pasta types. Kits containing enough ingredients to prepare severaldishes can also be prepared; preferably, such multiple dish kits wouldstill have the prepackaged ingredients in single dish amounts (e.g., afive dish kit would contain five separate packages of each ingredient).

Using the lasagna kit, alternating layers of the tomato based sauce,uncooked or partially precooked lasagna noodles, ricotta cheese blend,and, if desired, shredded cheese are placed in a baking dish. Theimproved spreadability of the present ricotta cheese blends makes thepreparation of such lasagna significantly easier. Of course, otherlayers may also be included, such as, for example, pepperoni or othermeat products, and second cheeses. The optional layers may be suppliedas packaged components within the kit or obtained separately by theconsumer. The completed layered preparation is then baked in an oven.The kit is formulated such that the water content of the cheeses and thetomato sauce is sufficient to rehydrate the lasagna noodles. Usingpartially precooked lasagna noodles can reduce the cooking time and/orthe water required to cook the dish.

The following examples are intended to illustrate the invention and notto limit it. Unless otherwise indicated, all percentages are by weight.

EXAMPLE 1

A ricotta blend was prepared containing ricotta cheese (about 59percent), Philadelphia brand Neufchatel cheese (about 20 percent),grated Parmesan cheese (about 2.1 percent), dried sweet whey (about 2.5percent), salt (about 1.4 percent), locust bean gum (about 0.3 percent).spices (about 2.3 percent), lactic acid (about 0.4 percent), sorbic acid(about 0.2 percent), and water (about 11.8 percent))granulated garlic,granulated onion, and parsley flakes. The blend was processed to 165° F.in a laydown cooker with steam injection for a period of about 2minutes. The spreadable ricotta blend was subjected to challengeexperiments using Clostridium botulinum. There was no growth ortoxigenesis of C. botulinum during 40 weeks at 55° F.

EXAMPLE 2

An Italian seasoned ricotta blend containing ricotta cheese (about 45percent), Philadelphia Neufchatel cheese (about 11 percent), milk fat(about 3 percent), dried sweet whey (about 3.8 percent), sodium chloride(about 1.5 percent), locust bean gum (about 0.3 percent), lactic acid(about 0.6 percent), spices (about 2.4 percent), corn flour (about 3percent), sorbic acid (about 0.2 percent), titanium oxide (about 0.5percent), and water (about 29 percent) was prepared. The blend wasprocessed to 165° F. in a laydown cooker for about 2 minutes. Thestabilized ricotta blend has stability upon storage at refrigeratedtemperature (i.e., about 55° F.) similar to that of Example 1. Ascompared to the ricotta cheese alone, the stabilized ricotta blend wassignificantly easier to spread.

EXAMPLE 3

An American seasoned ricotta blend containing ricotta cheese (about 45percent), Philadelphia Neufchatel cheese (about 11 percent), milk fat(about 2 percent), dried sweet whey (about 3.8 percent), sodium chloride(about 1.5 percent), locust bean gum (about 0.3 percent), lactic acid(about 0.6 percent), spices (about 2.3 percent), corn flour (about 3percent), sorbic acid (about 0.2 percent), titanium oxide (about 0.5percent), and water (about 30 percent) was prepared. The blend wasprocessed to 165° F. in a laydown cooker for about 2 minutes. Thestabilized ricotta blend has stability upon storage at refrigeratedtemperature (i.e., about 55° F.) similar to that of Example 1. Ascompared to the ricotta cheese alone, the stabilized ricotta blend wassignificantly easier to spread.

We claim:
 1. A method of preparing a stabilized ricotta cheese blend,said method comprising preparing a ricotta cheese blend consisting ofricotta cheese, salt, a preservative, and a non-ricotta cheese selectedfrom the group consisting of Neufchatel cheese, Parmesan cheese, Romanocheese, Cheddar cheese, Mozzarella cheese, Provolone cheese, creamcheese, and mixtures thereof; treating the ricotta cheese blend at atemperature in the range of 160° F. to 170° F. for a time sufficient toprovide the stabilized ricotta cheese blend; and adding sufficientedible acid to the ricotta cheese blend or to the stabilized ricottacheese blend to provide a pH of about 4.8 to about 5.2 for thestabilized ricotta cheese blend; wherein the stabilized ricotta cheeseblend has a shelf life stability against the growth of Clostridiumbotulinum of at least 20 weeks and is spreadable.
 2. The method asdefined in claim 1, wherein the treatment time is about 15 seconds toabout 5 minutes.
 3. The method as defined in claim 2, wherein the edibleacid is lactic acid, pyruvic acid, acetic acid, citric acid, tartaricacid, phosphoric acid, or mixtures thereof.
 4. The method as defined inclaim 2, wherein the preservative sorbic acid or a salt thereof.
 5. Themethod as defined in claim 1, wherein the treatment temperature is about165° F. and wherein the treatment time is about 1to about 4 minutes. 6.The method as defined in claim 1, wherein the blend of ricotta cheesecontains about 40 to 50 percent ricotta cheese, about 1 to 2 percentsalt, about 8 to about 12 percent of the non-ricotta cheese, and about0.1 to about 0.4 percent of the preservative; and wherein the edibleacid is sufficient to provide a pH of about 4.9 to about 5.1 for thestabilized ricotta cheese blend.
 7. A stabilized ricotta cheese blend,wherein the stabilized ricotta cheese blend is prepared by a methodcomprising preparing a ricotta cheese blend consisting of ricottacheese, salt, a preservative, and a non-ricotta cheese selected from thegroup consisting of Neufchatel cheese, Parmesan cheese, Romano cheese,Cheddar cheese, Mozzarella cheese, Provolone cheese, cream cheese, andmixtures thereof; treating the ricotta cheese blend to a temperature inthe range of 160° F. to 170° F. for a time sufficient to provide thestabilized ricotta cheese blend; and adding sufficient edible acid tothe ricotta cheese blend or to the [spreadable,] stabilized ricottacheese blend to provide a pH of about 4.8 to about 5.2 for thestabilized ricotta cheese blend; wherein the stabilized ricotta cheeseblend has a shelf life stability against the growth of Clostridiumbotulinum of at least 20 weeks and is spreadable.
 8. The stabilizedricotta cheese blend as defined in claim 7, wherein the edible acid issufficient to adjust the pH of the stabilized ricotta cheese blend tobetween about 4.9 and about 5.1, and the edible acid is lactic acid,pyruvic acid, acetic acid, citric acid, tartaric acid, phosphoric acid,or mixtures thereof.
 9. The stabilized ricotta cheese blend as definedin claim 7, wherein the preservative is sorbic acid or a salt thereof.10. The stabilized ricotta cheese blend as defined in claim 7, whereinthe blend of ricotta cheese contains about 30 to about 90 percentricotta cheese, about 1 to about 2 percent salt, about 0 to about 30percent of the non-ricotta cheese, and about 0.1 to about 0.4 percent ofthe preservative; and wherein the edible acid is sufficient to provide apH of about 4.8 to about 5.2 in the stabilized ricotta cheese blend;wherein the preservative is sorbic acid or a salt thereof; and whereinthe edible acid is lactic acid, pyruvic acid, acetic acid, citric acid,tartaric acid, phosphoric acid, or mixtures thereof.
 11. The stabilizedricotta cheese blend as defined in claim 7, wherein the blend of ricottacheese contains about 40 to about 50 percent ricotta cheese, about 1 toabout 2 percent salt, about 8 to about 12 percent of the non-ricottacheese, and about 0.1 to about 0.4 percent of the preservative; andwherein the edible acid is sufficient to provide a pH of about 4.9 toabout 5.1 for the stabilized ricotta cheese blend.